'Cheers bitches': Birthday grandma becomes viral star

That is exactly what happened when South Australian photographer Brigitte filmed her grandma in a pre-birthday video on Facebook.

The smile-inducing video shows the birthday girl trying to say the phrase "cheers bitches" to much laughter, trying to configure balloons to add up to her coming age, and having a crack at her first 'cake smash'.

"With my hands," Brigitte's grandmother asks with much incredulity when she's told how to perform a 'cake smash'.

The soon-to-be 90-year-old then shows she doesn't need much cajoling when she grabs the cake with both hands and takes a massive bite.

The video has since racked up 1.2 million views, over 16,000 reactions and nearly 13,000 shares.